FB_VN_ReadRegister_REAL
This FB reads a REAL register from the camera. Requires an open control channel (e.g. by calling FB_VN_GevCameraControl.OpenCamera() before)
Syntax
Definition:
FUNCTION_BLOCK FB_VN_ReadRegister_REAL
VAR_INPUT
nAddress : GVCP_REGISTER_ADDRESS;
nEndian : UINT;
bRead : BOOL;
nTimeout : TIME;
END_VAR
VAR_OUTPUT
fValue : REAL;
bBusy : BOOL;
bError : BOOL;
nErrorId : UDINT;
END_VAR
VAR
oidITcVnGevImageProvider : OTCID;
END_VAR
Inputs
|
Name |
Type |
Default |
Description |
|---|---|---|---|
|
nAddress |
|
The address of the register that should be read | |
|
nEndian |
UINT |
|
OPTIONAL: The endianness of the register. 0 = Big, 1 = Little. Default: 0 |
|
bRead |
BOOL |
|
Reading the register is triggered by a rising edge at this input. |
|
nTimeout |
TIME |
VISION_ADS_TIMEOUT |
Indicates the time before the function is cancelled. |
Outputs
|
Name |
Type |
Description |
|---|---|---|
|
fValue |
REAL |
The read value |
|
bBusy |
BOOL |
This output remains TRUE until the function block has executed a command, but at the longest for the duration supplied to the 'nTimeout' input. While bBusy = TRUE, no new command will be accepted at the inputs. |
|
bError |
BOOL |
This output is switched to TRUE as soon as an error occurs during the execution of a command. The command-specific error code is contained in ‘nErrorId’. If the function block has a timeout error, 'bError' is TRUE and 'nErrorId' is 1861 (hexadecimal 0x745). Is reset to FALSE by the execution of a command at the inputs. |
|
nErrorId |
UDINT |
Contains the ADS error code or the command-specific error code of the last executed command. Is reset to 0 by the execution of a command at the inputs. |
Further information
 | Open camera Control Channel needed! The Control Channel of the GigE Vision camera must be open in order to be able to use this function block. In addition, some camera parameters can only be changed if the image acquisition is stopped. It is therefore recommended to place the camera in the state TCVN_CS_OPENED first. |
Parameter
nAddress
The register address identifies the camera register to be addressed. It is of the type GVCP_REGISTER_ADDRESS, which is an alias of the type UDINT. Thus, all register addresses have a size of 4 bytes. The register address of a camera parameter can be seen at the respective point in the configuration tree of the GigE Vision camera instance:
nEndian
Endianess describes the order in which the bytes of a camera register are arranged. This does not need to be considered any further in terms of the application and can be adopted as a property of the respective parameter of the configuration tree of the GigE Vision camera instance:
A Big Endian is represented by nEndian := 0 and a Small Endian by nEndian := 1. Big Endian is the default.
Samples
Required License
TC3 Vision Base
System Requirements
Development environment | Target platform | PLC libraries to include |
|---|---|---|
TwinCAT V3.1.4024.54 or later | PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU | Tc3_Vision |